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Discussion Starter #1
A few months ago I got Linda Youngblood, of Manatee Sports, to order me a hundred .280 Remington cases made by Winchester. When they came in they were shiney nickle plated...pretty. Last week I dug them out, ran into the sizer to iron out the necks and put together 20 with my favorite load. This load is up near the top with 150 gr Ballistictips. Hank and I went up to the range, my main purpose to test some 125 Sierra and 180 Nosler BT in my new Ruger No1 Light Sporter. Just before we pulled out of the range to come home, I decided to crank out some rounds in the .280...The first shot out didn't feel right...Nep, you guess it..PRESSURE! The primer was flatten out bad, with cratering! I put the rifle up and when I came home, sat down to figure the problem out. My first thought was, that in my old age, I messed up on my powder setting...I pulled bullets and checked..nope, right on the 50.5 charge. O.K., maybe the necks on that nickle stuff was too thick (as can happen with pistol brass)...I miked the OD of the nickle brass loaded round Vs a brass case loaded round...The same! Now I was really concerned! I always trim/inside neck ream all my once fired brass. Since new brass is ready sized, I wait until once fired. I set up my Forster, adjusted it with a case I keep that is trimed to length..and started to trim/ream...Eureka!..These new cases were thousandths too long in the neck!!! What was happening was I was forcing these loaded rounds into the end of the chamber and swaged the loaded rounds neck..ergo, too tight bullet release = pressure! I put a few loads together in this trimmed cases, went out on my deck, and cranked them into an old stump in the back of our place...normal in all respects. We can not expect the companies to make everthing right. If this brass had run through the factory loading machines, the inspection/trim station would have alarmed. Like we say, "s--- happens!" everyone watch this on the new brass that's coming out..it did not go through the final inspection/trim set on the loading machines...I don't care what the factory says..I've been there on the floor!
Best Regards from the Hammock....James  

(Edited by James Gates at 1:30 pm on Jan. 20, 2001)
 

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James,

Great heads up. I know I'm picky but full length size and measure all my new brass before loading. My last batch of Starline 44 magnum brass was quite short right out of the box. Perhaps they're prepared to fall on the short side instead of long. You just can't be to careful.
 

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Thanks Jim


I'm very glad that no catastrophic incident happened. I'm just getting to know you. <!--emo&;)--><img src="http://beartoothbullets.com/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'><!--endemo-->


I've gotten into the habit of using the Lee Trimmer Pilots on all new cases to check length and/or square up the case mouths. They're quick and easy to use. I also like to fully size them first before loading.


Regards

:cool:
 

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Discussion Starter #4
Contender...You know I had forgotten those Lee trimmer pilots would slide in on a new or sized case. Checked it and sho'nuf they do...Thanks for reminder to my Old Head! You are correct..we can't assume anything in quality any more, except Marshall's bullets and policy!
Best Regards from The Hammock....James
 

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James, even if you have measured how meny thousandhs too long for YOUR rifle these cases were I wouldn´t role out that casevolym also played a role. I have never met a factoryrifle that couldn´t take a case some thousandhs longer than max. Often 20-30. I use to make 222 and 308 cases from 223 and 30-06 to get them long enough.
Goran
 

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Discussion Starter #6
Goran....Right you are..I checked the case volume (of water) against the same in brass case. They matched. I checked the headspace...OK. The only thing I found different was the length of neck (it was too long)...Trimed to the length of my brass cases....loaded the same load as brass cases...fired them, with normal pressre signs. The only thing I can figure is..the too long necks were cramping against the front of the chamber and restricting bullet release ? If it had been in a bolt gun or single shot I would have felt the resistance, but it was in a Rem.7400. That bolt slams hard!
Best Regards from The Hammock.....James
 

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James, you learned a valuable lesson, thank God you did not have serious consequences.  Over the last 32 years of reloading I have seen this happen more times than I care to remember.  Anytime you get new components you really need to check them out and make sure they are within specs.  Sometimes, new lots of brass may be thicker or thinner, resulting in more or less case volume and presto, pressure problems.  If I am getting new brass, same manufacture, I like to prep the cases as normal, trim and all that stuff, and then weigh them compared to an older fired case.  If there is much difference in weight, I reduce the load and work up again.  A difference in weight of more than two or three grains on average of a 30-06 sized case (I like to weigh at least 10 cases each and take an average value), especially if the new cases weigh more, can indicate that the new case is thicker and there may be less internal volumn, ergo, the pressures will be higher.  I am sure you already know this, but whenever switching ANY component-bullet brand, primer brand, case manufacture-ALWAYS start over from the start load and work it up again.  When I first started loading I figured I knew it all and the book warnings were for sissys.  I switched out the bullets in a 6mm Rem load from a Sierra to Nosler Partition without working back up the load.  Sure it was near max, but hey, I was 13 and INVINCIBLE.  Took a rubber mallet to beat the bolt open.  I may have been ignorant, but I wasn't stupid, and I still haven't forgotten that lesson.
 

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Discussion Starter #8
You know...There's another factor to watch for on these auto load rifles...Rem. seris of 740 through 7400 and BAR 1&2... and that's powder burning rate vs gas port location. I saw the buffers beat out of 2 BAR's with IMR4831 loads. I normally advise mid burn powders (IMR4064 & IMR 4895) for these auto rifles. You lose a little velocity, but much better for the firearm. I "thought" Remington closed down the opening into the gas cylinder on the new rifles, but they didn't. Factory load .280's are well below what Powley even says.I'm still leary of the nickel rifle cases.I don't think bullet release is the same with those harder cases, although I know they are just plated.
Best Regards from the Hammock...James

(Edited by James Gates at 7:55 pm on Feb. 3, 2001)
 

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"Just plated?"

In an ideal world, plating would consist of nothing more than adding a thin layer of whatever metal to the top of the base metal. However, plating is a very complex process. In order to get the nickel to stick to brass, for example, as I recall they first plate a thin layer of copper on it. This is called a 'copper strike' and is on the order of only 50 millionths of an inch thick. (Without this, the zinc in the brass interferes with the development of the copper-nickel intermetallic compound responsible for adhesion of the nickel.) Then they plate the nickel. And that doesn't count all the pre-etching ('activation' and 'cleaning') steps that are required.

All of these things involve the use of highly-reactive chemicals, which can have all sorts of unintended consequences. For example, many alloys suffer from what is called 'hydrogen embrittlement' when they are plated. I'm at home and don't have my metals handbooks available, so I don't know if this happens to brass, but I recall reading several places that nickel plated cases are harder and have a shorter life than plain brass. I am willing to bet that hydrogen embrittlement, or some similar effect caused by all the processing, is the cause.

Your suspicion of nickel plated cases is very well-founded, in my humble opinion. Stick with plain brass, and you eliminate a whole bunch of possible problems resulting from plating. Worst of all, these secondary effects often vary from lot to lot, depending on all manner of incidental (and often uncontrolled) factors.

As for long cases causing pressure increases, on p. 35 of "Modern Reloading," Richard Lee says: "It boils down to: cases do get longer, and must be trimmed or they will pinch the bullet at the end of the gun's chamber. This will cause higher and possibly dangerous pressures." It is not really that they are crimped any tighter. What happens is that the over-length brass has nowhere to go when the round is fired; when it tries to expand to fill the chamber, the end of the case gets caught up on the forcing cone and/or the ball seat, pinching the bullet. The bullet then is swaged down to squeeze through this now significantly-undersized orifice. This is where the extra pressure comes from. Especially if you are shooting jacketed bullets. (Can't help accuracy either, I suspect, as it is equivalent to firing an undersized bullet.)
 

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Discussion Starter #10
All of you are correct....Here's the realriddle...I checked my notes and I did square off the necks after I ran the expander ball in to roundout the necks, but didn't set the trim length....I still believe they were Much too long. I feel pretty stupid about all this!.....James
 

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James,

I have had much the same experience with two lots of cases in the past. Yep, I didn't lear the first time. NOW, I never use any new cases unless I examine them dimensionally and volume wise.

The worst case I have seen was when I sold a 22 hbornet to a friend's son about 25 years ago. When i bought the rifle I also bought a 1000 new cases of a single lot. These were the only cases I ever used with that rifle. My friend took the recipe for my loads and purchased the equivalent components. My fiend is a very experienced and very careful reloader who saw no reason to try to push those 45 grain bullets at extreme velocities.

When Friend, son and I went to the range, I was sitting at the bench position next to Ken, the son. His father was standing some  positions farther down shooting his 577 Nitro Express double at fifty yard targets and knocking down the hundred yard targets with  pebbles thrown into the air by the large bullets.

Ken proudly loaded his new single shot and fired a round on the two hundred yard gong. It rang allright. He loaded again after placing the empty mouth down in the plastic cartridge box. I happened to glance over and noticed that there was no primer in the primer pocket just a big (well as big as it can be on the base of that little case) black smudge.

Needless to say I got him to unload while we checked things out. After checking everything we found that the volume of the new cases was several percent less than the very old cases that I had been shooting in that rifle for maybe a decade.
Regards,
Dave
 
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